Steps

Step #1:

You can make the cake to any scale you want, but if you use the same one I did, you'll get a 65" long cake that's 4.5" high with a 1/3" block scale. By "block," I mean the measuring unit of everything Mario. A block of bricks is one block, which is also the size (or multiplier thereof) of most other things. That means each little item you carve out of fondant will have to fit within a 1/3" square.

Use the image linked in the guide to place pieces on the cake. All the images here were first attacked by hungry players.

Step #2:

If you cut two half sheet cakes into thirds, you'll have six 4.3-4.5" wide pieces, depending on your cutting precision and the evenness of your baking. Place five of these lengths end to end to make the actual cake.

Frost it lightly and smoothly with buttercream. It's not worth trying to get it in the fridge first.

Step #3:

Cover the entire length of the cake in sky blue fondant. If you're really good, you can roll the entire length at once. More likely, you'll have to smooth some seams. Use Crisco to help them blend together.

Step #4:

Here are all the tiny pieces you'll need to dye fondant for, then roll out and cut. Make markings on clouds and bricks with food markers. (The pieces in this picture have been attacked by hungry children and aren't what we'd call properly aligned.)

Bushes similarly come in one-hump, two-hump, and three-hump varieties. You'll need 4, 4, and 3, respectively as well as two "half-humps."

Hills come in size "1" and size "3," which I named based on the marks on them. You'll need 5 size 1 and 5 size 3.

You can either do the brick sections all as single blocks, or you can do the multi-block brick lengths as chunks. If you do, you'll need 10 1-block segments, 3 2-block, 2 3-block, and one 8-block. You'll also need 13 question mark blocks. Draw the question marks on with red markers. For the ground that runs along the bottom, you'll need 65" minus a few spots where Mario can fall through the hole.

The different type of blocks that Mario jump up like stairs can either be cut all as one or individually as squares. If individually, you'll need 89.

Pipes are not as consistently measured in height as other things, so that's why I recommended printing at your chosen scale to measure.

You'll also need an assortment of Goombas, coin(s), a star, a one up mushroom, fire flower, size mushroom, and a turtle. Don't forget the castle and the flag!